HomeRoast Digest


Topic: 12 oz. w/Stir-Crazy (6 msgs / 250 lines)
1) From: John Wanninger
Last night I decided to try a couple of roasts with a
modified thermostat stir-crazy.
Times and Temps are approximate
Ambient Temp:68F
Trial#1 : Columbian Popayan Colsuaves
 (I used what I had left in the bag - I'm guessing just shy of 10 oz.)
  Preheat to 350F
  00:00 to 06:00 : 350F
  06:00 to 07:00 : 380F
  07:00 to 10:00 : 400F ' 1st crack started at 09:30
  10:00 to 12:30 : 420F  ' Stopped at just shy of 2nd crack (I think)
  Ending weight: 8-1/4 oz.
Trial#2 : Kenya Eaagads
  Starting weight: 12 oz.
  Preheat to 350F
  00:00 to 07:00 :  350F
  07:00 to 08:00 :  380F
  08:00 to 09:00 :  400F
  09:00 to 10:00 :  410F  ' 1st crack started at 09:55
  10:00 to 11:00 :  425F
  11:00 to 13:15 :  440F   ' Just shy of 2nd crack?
  Ending weight: 10-1/8 oz. (weight loss just under 16%)
I tried the Columbian this morning, it was very good, but I should have
roasted   another batch with hot-air for a cupping comparison.  Compared to
what I remember of the hot-air roast, I'd guess this batch had diminished
acidity and aroma. It still had a slight fruitiness, good body, good
complexity, and was by no means dull.  It did lose some of the fireworks
however.  I'll try it again tomorrow and see if aroma strengthens.
I'll try roasting some of the Kenyan Eaagads tonight via hot-air for a
comparison cupping this weekend.
In terms of Roast Evenness:
The Columbian was as good as or better then any air roast.
The Kenyan was almost, but not quite as good as most air roasts.
I'm curious to see if I can get good roasts with batches exceeding 12 oz.
I'm guessing both of these coffees may be better suited to hot-air roasting,
but it's always fun to experiment, as one never knows until one tries...
In the past, I've had delicious results by blending air-roasts with
conduction roasts of the same bean type/origin.
John
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

2) From: Ryuji Suzuki -- JF7WEX
This is very interesting. You are using the $30 popcorn popper, right?
How did you measure the temperature? Of the air, or of the bottom
plate? (I guress you can't really put any thermometer on the surface
because of the stirrer.) Could you raise the temperature more rapidly,
preferrably to a slightly higher point? (e.g. 450F)
From: "John Wanninger" 
Subject: +12 oz. w/Stir-Crazy
Date: Thu, 17 May 2001 14:57:02 -0500
<Snip>
This sounds like the right thing to try.
<Snip>
My guess is that this is partly because the roast is taking too long
time at a lower temperature. I am also thinking about side-by-side
comparison of my oven roasting against fluid bed type roasters...
Ryuji Suzuki
--
Ryuji Suzuki
"Slow but steady wins the race." (anonymous, 19c.)
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

3) From: John Wanninger
<Snip>
Yes (actually $6 from thrift store)
<Snip>
I've got a thermocouple attached to the underside of the heated aluminum
"basin" or  plate in which the beans rest.  The thermostat has been
bypassed.  I'm using an OMRON temperature controller instead.  I'd like to
come up with a cheaper thermostat to make the mod cheaper and easier for
those who don't have a temperature controller laying around.
I wonder if a block with a hole could be attached under the  base which
might allow a plug-in style adjustable frypan type thermostat/control cord
(which I've seen readily available in some stores). As long as you could
couple enough heat from the bottom of the plate to the probe of the control,
you could probably correlate dial setting to actual plate temperature and
have an inexpensive controller (and roaster!).
And yes, I could raise the temperature more rapidly. I don't know yet whats
the best temperature profile to follow.  I guess I'm shooting for an
approximate 12min roast time to city/full city.  I thought I might try the
approach I believe the Alp takes, which is (I think) to slowly bring the
beans up to temperature before 1st crack.
I've had roasts as short as 9 minutes, and as long as 15 minutes. Lots of
experimenting yet to do!
John
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

4) From: Angelo

5) From: Angelo
John,
I got this url from the alt.coffee group. Thought you might find something
here to help in your quest for an affordable controller. I, for one, would
be very interested, as I have a stir-crazy sitting in the back room,
waiting.
When first got it, it seemed to roast pretty well. Now, that I heard it's
not hot enough, guess what?...it's not hot enough.:-).http://www.mcshaneinc.com/html/Prod_TempConMostPop.htmlCiao,
Angelo
|
|
| >
| > This is very interesting. You are using the $30 popcorn popper, right?
|
| Yes (actually $6 from thrift store)
|
| >
| > How did you measure the temperature? Of the air, or of the bottom
| > plate? (I guress you can't really put any thermometer on the surface
| > because of the stirrer.) Could you raise the temperature more rapidly,
| > preferrably to a slightly higher point? (e.g. 450F)
|
| I've got a thermocouple attached to the underside of the heated aluminum
| "basin" or  plate in which the beans rest.  The thermostat has been
| bypassed.  I'm using an OMRON temperature controller instead.  I'd like to
| come up with a cheaper thermostat to make the mod cheaper and easier for
| those who don't have a temperature controller laying around.
|
| I wonder if a block with a hole could be attached under the  base which
| might allow a plug-in style adjustable frypan type thermostat/control cord
| (which I've seen readily available in some stores). As long as you could
| couple enough heat from the bottom of the plate to the probe of the
control,
| you could probably correlate dial setting to actual plate temperature and
| have an inexpensive controller (and roaster!).
|
| And yes, I could raise the temperature more rapidly. I don't know yet
whats
| the best temperature profile to follow.  I guess I'm shooting for an
| approximate 12min roast time to city/full city.  I thought I might try the
| approach I believe the Alp takes, which is (I think) to slowly bring the
| beans up to temperature before 1st crack.
|
| I've had roasts as short as 9 minutes, and as long as 15 minutes. Lots of
| experimenting yet to do!
|
|
| John
|
|
|
| homeroast mailing list
|http://lists.sweetmarias.com/mailman/listinfo/homeroast">http://lists.sweetmarias.com/mailman/listinfo/homeroasthomeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast

6) From: John Wanninger
Thanks for the link Angelo.  Looks like they have some neat, reasonably
priced controllers.  Especially nice are the RS232 models for computer
control, at under $200 for a 15A unit, which would easily handle a
stir-crazy (or a hot-air unit).  This is a great application for a
"worthless" old discarded personal computer.
For under $100, I see they have a few controllers that would also do the job
, although with fewer features and less convenience.
For those on a tighter budget, I'd like to come up with a cheap popper
conversion, that the average basement/garage tinkerer could do for under
$20.  That way, even if one bought a new Stir-Crazy, the total cost would
stay under $50, which can eases the budget and improves the SAF(spousal
acceptance factor).
John
<Snip>
homeroast mailing listhttp://lists.sweetmarias.com/mailman/listinfo/homeroast


HomeRoast Digest